Fill note generator for electronic organ

Abstract

A fill note generator for use in electronic musical instruments such as electronic organs which include a keyboard having a solo portion customarily played by the right hand and an accompaniment portion customarily played by the left hand, and wherein the respective solo and accompaniment portions may be on separate manuals or on a single manual. A multiplexer scans the keys of the solo portion of the keyboard and generates a time division multiplexed solo data stream having keydown signals in discrete time slots for each actuated key of the solo portion of the keyboard. The keys of the accompaniment portion of the keyboard are interconnected so as to form twelve sets corresponding to the twelve pitches of the chromatic scale wherein the keys in each set are connected to a common output. A multistage shift register, which is synchronized with the multiplexer for the solo manual, has its load inputs connected to the outputs of the interconnected sets of accompaniment keys and produces on its output a fill note time division multiplexed data stream comprising keydown signals in time slots corresponding to the keydown signals loaded into its inputs from the outputs of the sets of accompaniment keys. The inputs, which are loaded once each scan of the solo portion of the keyboard, are recirculated in the shift register so that the pattern repeats itself once each octave of the scan of the solo portion of the keyboard.